Elongated substrates, such as wiring harnesses, fluid conduits, such as brake lines and fuel lines, and optical fiber bundles are often used in automotive, aerospace and marine environments where they are subjected to significant ambient vibration. In automotive applications, wiring harnesses in particular are pernicious sources of unwanted “rattle noise” due to their propensity to resonate in response to structure borne vibration caused by engine operation or irregularities of the road surface over which the vehicle is passing. Wiring harnesses typically extend substantially throughout the vehicle's passenger compartment where they distribute power and control signals from the engine compartment to the dashboard instruments, interior lights, radio, speakers, electric windows, electric door locks, the window defogging element and on to the trunk to power the tail lights and often an electric fuel pump which may be positioned in the fuel tank. Although the harness is intermittently attached to the vehicle structure, the lengths of the harness between attachment points will often resonate and rattle against the structure in response to relatively low-frequency vibrations within the range of human hearing and provide a source of noise, which is both annoying and a cause of concern to the vehicle occupants. Aside from the noise annoyance, vibration of wiring harnesses will cause fatigue failures of the wiring, solder joints or mechanical connectors, leading to electrical malfunctions, such as short circuits, which could result in a vehicle fire. The failure due to vibration and fatigue of other elongate substrates, such as fuel lines or brake lines, also has catastrophic potential. There is clearly a need for a device which will help damp vibration of elongated substrates and thereby reduce sympathetic vibration of the substrates and its resultant rattle noise and associated fatigue failures.